操作者在机床上测量和检査工件时必须：（ ）。

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SQL Error: select id,body,options from ***_enewstiku where sourceid='30404' and id < 2457968 and id<>'2457968' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='30404' and id > 2457968 and id<>'2457968' order by id asc limit 5